CN103935265A - Automobile body stability control system for electric automobile - Google Patents

Abstract

The invention discloses an automobile body stability control system for an electric automobile. A hierarchical control structure is adopted for the system. An upper layer controller aims at achieving yaw stability control, wherein the yawing moment required in the whole automobile movement process needs to be calculated, required signals are provided by sensors, and the required yawing moment can be calculated according to the signals and is compared with the practical value. The control target of a lower layer controller is achieved by ensuring that yawing moment instructions sent by the upper layer controller are distributed through braking force, wherein the lower layer controller controls motor moment distribution and the slip rate of wheels so that the required yawing moment can be obtained for an automobile and the automobile can stably run.

Description

A kind of vehicle body stabilizing control system of electronlmobil

Technical field

The present invention relates to new energy vehicle and control technology field thereof, relate in particular to a kind of vehicle body stabilizing control system of electronlmobil.

Background technology

The today of increasingly sharpen at energy scarcity, environmental pollution is day by day serious, the development trend of the times of electronlmobil, back-wheel drive electronlmobil also becomes the focus of research.

Single-row front and back seat narrow long type battery-driven car is a kind of novel battery-driven car moulding, and it possesses soon, spirit, little feature, and not only suitable for city trip, cross-country traveling ability, convenient high speed and the flying power of stopping but also possessing traditional vehicle, become a kind of novel electric vehicle trend.

Car load stabilizing control system is extremely important for back-wheel drive electronlmobil, its effect is mainly, ensure stability and the controllability of automobile in the time turning, brake and drive, assist chaufeur to control vehicle in extreme manoeuvre situation, prevent that vehicle from occurring too much or understeering, the yaw velocity of vehicle is controlled in the scope that chaufeur can grasp.

At present, comparatively effective method is not stablized the method for controlling to the vehicle body of electronlmobil, thereby has certain potential safety hazard.

Summary of the invention

The object of this invention is to provide a kind of vehicle body stabilizing control system of electronlmobil, make vehicle obtain needed yaw moment, guarantee that vehicle can stably travel.

The object of the invention is to be achieved through the following technical solutions:

A vehicle body stabilizing control system for electronlmobil, this system comprises: sensor unit, Car Electronic Control unit ECU, accelerator module, brake unit, electric machine controller and wheel hub motor;

Wherein, described sensor unit, for the speed of a motor vehicle, wheel speed, yaw velocity, lateral acceleration and the steering wheel angle information of collection vehicle;

Described accelerating module, give it the gun for sending vehicle described in Acceleration Signal control;

Described brake module, travels for sending automobile low-speed described in speed-slackening signal control;

Described vehicle ECU unit, for the information collecting according to described sensor unit, and the signal that sends of accelerator module and brake unit, and learn model based on two degrees of freedom steering power and calculate the yaw velocity of expection; Difference between the actual yaw velocity collecting according to the yaw velocity of described expection and sensor unit is again calculated the needed yaw moment of vehicle current time;

Described electric machine controller, controls described wheel hub motor for the yaw moment calculating according to described vehicle ECU unit, thereby controls the slip rate of each wheel.

As seen from the above technical solution provided by the invention, system adopts heterarchical architecture, the target of upper strata controller is to realize the stable control of yaw, need calculate needed yaw moment value in car load motion process, needed signal is provided by sensor, according to these signals, can calculate needed yaw moment value, and with actual value comparison.The control target of lower floor's controller is to ensure that the yaw moment instruction that upper strata controller sends is achieved by the distribution of braking force, the slip rate of lower floor's controller control motor torque distribution and wheel, make vehicle obtain needed yaw moment, automobile can stably travel.

Brief description of the drawings

In order to be illustrated more clearly in the technical scheme of the embodiment of the present invention, below the accompanying drawing of required use during embodiment is described is briefly described, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, do not paying under the prerequisite of creative work, can also obtain other accompanying drawings according to these accompanying drawings.

The schematic diagram of the vehicle body stabilizing control system of a kind of electronlmobil that Fig. 1 provides for the embodiment of the present invention one;

The function model figure of a kind of vehicle body stabilizing control system that Fig. 2 provides for the embodiment of the present invention two.

Detailed description of the invention

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, obviously, described embodiment is only the present invention's part embodiment, instead of whole embodiment.Based on embodiments of the invention, those of ordinary skill in the art, not making the every other embodiment obtaining under creative work prerequisite, belong to protection scope of the present invention.

Embodiment mono-

The schematic diagram of the vehicle body stabilizing control system of a kind of electronlmobil that Fig. 1 provides for the embodiment of the present invention one.As shown in Figure 1, it mainly comprises:

Sensor unit 100, Car Electronic Control unit ECU111, accelerator module 106, brake unit 107, electric machine controller 109 and wheel hub motor 110;

Wherein, described sensor unit 100, for the speed of a motor vehicle, wheel speed, yaw velocity, lateral acceleration and the steering wheel angle information of collection vehicle;

Described accelerating module 106, give it the gun for sending vehicle described in Acceleration Signal control;

Described brake module 107, travels for sending automobile low-speed described in speed-slackening signal control;

Described vehicle ECU unit 111, for the information collecting according to described sensor unit 100, and the signal that sends of accelerator module 106 and brake unit 107, and learn model based on two degrees of freedom steering power and calculate the yaw velocity of expection; Difference between the actual yaw velocity collecting according to the yaw velocity of described expection and sensor unit is again calculated the needed yaw moment of vehicle current time;

Described electric machine controller 109, controls described wheel hub motor 110 for the yaw moment calculating according to described vehicle ECU unit 111, thereby controls the slip rate of each wheel.

Further, described sensor unit 100 comprises: steering wheel angle sensor 103, wheel speed sensors 101, car speed sensor 102, yaw-rate sensor 105 and lateral acceleration sensor 104.

Further, described two degrees of freedom steering power model comprises:

$\begin{array}{c}m({\stackrel{\·}{V}}_y+V_x\stackrel{\·}{\mathrm{\Ψ}})=\frac{C_{\mathrm{af}}}{C_{\mathrm{\λf}}}(\frac{{\mathrm{Fb}}_{\mathrm{lf}}}{{\mathrm{\λ}}_{\mathrm{lf}}}+\frac{{\mathrm{Fb}}_{\mathrm{rf}}}{{\mathrm{\λ}}_{\mathrm{rf}}})\cos {\mathrm{\δ}}_w({\mathrm{\δ}}_w-{\mathrm{\β}}_f)+\frac{C_{\mathrm{ar}}}{C_{\mathrm{\λr}}}(\frac{{\mathrm{Fb}}_{\mathrm{lr}}}{{\mathrm{\λ}}_{\mathrm{lr}}}+\frac{{\mathrm{Fb}}_{\mathrm{rr}}}{{\mathrm{\λ}}_{\mathrm{rr}}}){\mathrm{\β}}_r\\ -({\mathrm{Fb}}_{\mathrm{lf}}+{\mathrm{Fb}}_{\mathrm{rf}})\sin {\mathrm{\δ}}_w\end{array};$

$\begin{array}{c}{J}_v\stackrel{\·\·}{\mathrm{\Ψ}}=-[\frac{C_{\mathrm{af}}}{C_{\mathrm{\λf}}}(\frac{{\mathrm{Fb}}_{\mathrm{lf}}}{{\mathrm{\λ}}_{\mathrm{lf}}}+\frac{{\mathrm{Fb}}_{\mathrm{rf}}}{{\mathrm{\λ}}_{\mathrm{rf}}})L_f\cos {\mathrm{\δ}}_w-\frac{C_{\mathrm{af}}}{C_{\mathrm{\λf}}}(\frac{{\mathrm{Fb}}_{\mathrm{lf}}}{{\mathrm{\λ}}_{\mathrm{lf}}}+\frac{{\mathrm{Fb}}_{\mathrm{rf}}}{{\mathrm{\λ}}_{\mathrm{rf}}})L_s\sin {\mathrm{\δ}}_w]({\mathrm{\δ}}_w-{\mathrm{\β}}_f)\\ +\frac{C_{\mathrm{ar}}}{C_{\mathrm{\λr}}}(\frac{{\mathrm{Fb}}_{\mathrm{lr}}}{{\mathrm{\λ}}_{\mathrm{lr}}}+\frac{{\mathrm{Fb}}_{\mathrm{rr}}}{{\mathrm{\λ}}_{\mathrm{rr}}})L_r{\mathrm{\β}}_r+({\mathrm{Fb}}_{\mathrm{lf}}+{\mathrm{Fb}}_{\mathrm{rf}})L_f\sin {\mathrm{\δ}}_w\\ +({\mathrm{Fb}}_{\mathrm{lf}}-{\mathrm{Fb}}_{\mathrm{rf}})L_s\cos {\mathrm{\δ}}_w+({\mathrm{Fb}}_{\mathrm{lr}}-{\mathrm{Fb}}_{\mathrm{rr}})L_s\end{array};$

Wherein, the quality that m is vehicle, V _ythe cross velocity of vehicle, for the transverse acceleration of vehicle, V _xfor the longitudinal velocity of vehicle, for the yaw velocity of vehicle, Fb _lf, Fb _rf, Fb _lr, Fb _rrbe respectively the size of the near front wheel, off front wheel, left rear wheel and off hind wheel braking force, λ _lf, λ _rf, λ _lr, λ _rrbe respectively the size of the near front wheel, off front wheel, left rear wheel and off hind wheel slip rate, C _af, C _arbe respectively the cornering stiffness of front and back wheel, C _{λ f}, C _{λ r}be respectively the longitudinal rigidity of front-wheel and trailing wheel, δ _wfor the deflection angle of wheel, J _vfor the rotor inertia of vehicle, for the yaw angle acceleration/accel of vehicle, β _f, β _rbe respectively the tyre slip angle of front-wheel and trailing wheel, L _f, L _rbe respectively the wheelbase of vehicle front and back wheel, L _sfor the half of car gage.

Further, the yaw moment of automobile is determined by braking force and the transverse force of automobile, the large I of braking force and transverse force is learned model by two degrees of freedom steering power and is calculated, specifically, two degrees of freedom steering power model has determined the size of four wheel slips, and braking force and transverse force can be calculated by the slip rate of wheel, and the braking force of automobile and transverse force are provided by four tires, the model HSRI tire model of tire, model is as follows:

Definition:

$H=\frac{\sqrt{{\mathrm{\λ}}^2{C}_{\mathrm{\λ}}^2+C_a^2{\left(\tan \mathrm{\α}\right)}^2}}{(1-\mathrm{\λ})\mathrm{\μ}{F}_N}$

In the time of H >=0.5

$F_s=\frac{C_a}{1-\mathrm{\λ}}(\frac{1}{H}-\frac{1}{{4H}^2})\tan \mathrm{\α}$ $F_B=\frac{{\mathrm{\λC}}_{\mathrm{\λ}}}{1-\mathrm{\λ}}(\frac{1}{H}-\frac{1}{{4H}^2})$

In the time of H<0.5

$F_s=\frac{C_a\tan \mathrm{\&alpha;}}{1-\mathrm{\&lambda;}}$ $F_B=\frac{{\mathrm{\&lambda;C}}_{\mathrm{\&lambda;}}}{1-\mathrm{\&lambda;}}$

Wherein, F _s, F _bbe respectively transverse force and the braking force of tire, the slip rate that λ is tire, C _a, C _λbe respectively cornering stiffness and the slippage rigidity of tire, F _nfor the normal pressure that tire is subject to, μ is the friction coefficient between tire and ground, the sideslip angle that α is tire.

Further, learn model and HSRI tire model according to two degrees of freedom steering power on it, can implement yaw Stable Control Strategy.

Further, described electric machine controller 109, also for according to the instruction of described vehicle ECU unit 111, in the time that Vehicular turn is not enough, increases the braking force of inside rear wheel wheel hub motor 110; Excessive when Vehicular turn, the braking force of front-wheel hub motor 110 outside increasing; And in the time that vehicle travels on the road surface lower than threshold value at adhesion value, reduce the braking force of the larger side wheel hub motor 110 of braking force.

Further, this system also comprises: driving console 108, in the time that described electric machine controller 109 is controlled wheel hub motor 110, described vehicle ECU unit 111 informs that by described driving console 108 chaufeur is just carrying out the stable control of vehicle body.

The system of the embodiment of the present invention adopts heterarchical architecture, the target of upper strata controller is to realize the stable control of yaw, need calculate needed yaw moment value in car load motion process, needed signal is provided by sensor, according to these signals, can calculate needed yaw moment value, and with actual value comparison.The control target of lower floor's controller is to ensure that the yaw moment instruction that upper strata controller sends is achieved by the distribution of braking force, the slip rate of lower floor's controller control motor torque distribution and wheel, make vehicle obtain needed yaw moment, automobile can stably travel.

Embodiment bis-

For the ease of understanding the present invention, below in conjunction with accompanying drawing 2, the present invention is described further.

In the embodiment of the present invention, vehicle stabilization control system is by vehicle ECU unit, the wheel speed sensors of four wheels, Vehicular yaw acceleration pick-up, vehicle side is to acceleration pick-up, steering wheel angle sensor, accelerator module, brake unit and wheel hub motor and controller composition thereof, sensor is mainly responsible for providing the existing condition signal of car load motion, vehicle ECU carries out the calculating of model in unit, be responsible for sending the control command signal of vehicle stabilization control system, wheel hub motor and electric machine controller are mainly responsible for controlling the rotating speed of wheel, the control of moment and the control of slip rate, carrying out active braking controls, guarantee that automobile can stably travel.

The function model figure of a kind of vehicle body stabilizing control system providing for the embodiment of the present invention as shown in Figure 2.

First the information, collecting according to vehicle sensors is calculated the yaw velocity of expection; Then, the yaw velocity of expection and actual yaw velocity (Vehicular yaw acceleration pick-up collects) are compared, according to its difference, after calculating required yaw moment, the yaw moment value of distribution is input in electric machine controller 109, and lock torque, slip rate by electric machine controller 109 to wheel are controlled.

Further, in Vehicle Driving Cycle process, the first value of read direction dish rotary angle transmitter 103 of vehicle ECU unit 111, judge that vehicle is not after straight-line travelling, vehicle ECU111 reads respectively four wheel speed sensors 101, car speed sensor 102, lateral acceleration sensor 104, yaw-rate sensor 105, the data such as the signal of the signal of accelerator module 106 and brake unit 107, learn model according to two degrees of freedom steering power, the calculating of the expectation values such as the yaw velocity that expect vehicle ECU unit 111, and with vehicle traveling process in actual signal make comparisons, in the time having deviation between actual value and expectation value, automobile is implemented to yaw Stable Control Strategy.

If need to implement yaw Stable Control Strategy, measure the difference of the actual yaw velocity of gained according to expection yaw velocity and yaw-rate sensor 105, calculate needed yaw moment of this moment of automobile, then by electric machine controller 109, wheel hub motor 110 is controlled, be that four wheels distribute corresponding braking force, thereby control the slip rate of each wheel, produce suitable yaw moment, automobile can be stablized and travel.In addition, now vehicle ECU111 can communicate with driving console 108, informs that driver is carrying out the stable control of vehicle body.

In the time of understeer, initiatively braking is controlled and can be passed through electric machine controller 109, increase the braking force of inside rear wheel wheel hub motor 110, now due to the variation of yaw moment, automobile can be got back on the running route of driver's expection, in the time that motor turning is excessive, initiatively braking is controlled and can be passed through electric machine controller 109, increase the braking force of outside front-wheel hub motor 110, and reduce the speed of automobile, change yaw moment, thus correct a mistake turn to attitude, automobile is got back on the running route of driver's expection.

When automobile travels on the road surface of low adhesion value (as icy roads), if the adhesive ability between each wheel and ground is inconsistent, when straight line brake, vehicle can be to the larger side sideslip of braking force, now, this active control system can pass through electric machine controller 109, suitably reduces the braking force of the larger side wheel hub motor 110 of braking force, makes running car on the circuit of expection.

The system of the embodiment of the present invention adopts heterarchical architecture, the target of upper strata controller is to realize the stable control of yaw, need calculate needed yaw moment value in car load motion process, needed signal is provided by sensor, according to these signals, can calculate needed yaw moment value, and with actual value comparison.The control target of lower floor's controller is to ensure that the yaw moment instruction that upper strata controller sends is achieved by the distribution of braking force, the slip rate of lower floor's controller control motor torque distribution and wheel, make vehicle obtain needed yaw moment, automobile can stably travel.

Those skilled in the art can be well understood to, for convenience and simplicity of description, only be illustrated with the division of above-mentioned each functional module, in practical application, can above-mentioned functions be distributed and completed by different functional modules as required, be divided into different functional modules by the inner structure of system, to complete all or part of function described above.

The above; only for preferably detailed description of the invention of the present invention, but protection scope of the present invention is not limited to this, is anyly familiar with in technical scope that those skilled in the art disclose in the present invention; the variation that can expect easily or replacement, within all should being encompassed in protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion with the protection domain of claims.

Claims (5)

1. a vehicle body stabilizing control system for electronlmobil, is characterized in that, this system comprises: sensor unit, Car Electronic Control unit ECU, accelerator module, brake unit, electric machine controller and wheel hub motor;

Wherein, described sensor unit, for the speed of a motor vehicle, wheel speed, yaw velocity, lateral acceleration and the steering wheel angle information of collection vehicle;

Described accelerating module, give it the gun for sending vehicle described in Acceleration Signal control;

Described brake module, travels for sending automobile low-speed described in speed-slackening signal control;

Described vehicle ECU unit, for the information collecting according to described sensor unit, and the signal that sends of accelerator module and brake unit, and learn model based on two degrees of freedom steering power and calculate the yaw velocity of expection; Difference between the actual yaw velocity collecting according to the yaw velocity of described expection and sensor unit is again calculated the needed yaw moment of vehicle current time;

Described electric machine controller, controls described wheel hub motor for the yaw moment calculating according to described vehicle ECU unit, thereby controls the slip rate of each wheel.

2. system according to claim 1, is characterized in that, described sensor unit comprises:

Steering wheel angle sensor, wheel speed sensors, car speed sensor, yaw-rate sensor and lateral acceleration sensor.

3. system according to claim 1, is characterized in that, described two degrees of freedom steering power is learned model and comprised:

$\begin{array}{c}m({\stackrel{\&CenterDot;}{V}}_y+V_x\stackrel{\&CenterDot;}{\mathrm{\&Psi;}})=\frac{C_{\mathrm{af}}}{C_{\mathrm{\&lambda;f}}}(\frac{{\mathrm{Fb}}_{\mathrm{lf}}}{{\mathrm{\&lambda;}}_{\mathrm{lf}}}+\frac{{\mathrm{Fb}}_{\mathrm{rf}}}{{\mathrm{\&lambda;}}_{\mathrm{rf}}})\cos {\mathrm{\&delta;}}_w({\mathrm{\&delta;}}_w-{\mathrm{\&beta;}}_f)+\frac{C_{\mathrm{ar}}}{C_{\mathrm{\&lambda;r}}}(\frac{{\mathrm{Fb}}_{\mathrm{lr}}}{{\mathrm{\&lambda;}}_{\mathrm{lr}}}+\frac{{\mathrm{Fb}}_{\mathrm{rr}}}{{\mathrm{\&lambda;}}_{\mathrm{rr}}}){\mathrm{\&beta;}}_r\\ -({\mathrm{Fb}}_{\mathrm{lf}}+{\mathrm{Fb}}_{\mathrm{rf}})\sin {\mathrm{\&delta;}}_w\end{array};$

$\begin{array}{c}{J}_v\stackrel{\&CenterDot;\&CenterDot;}{\mathrm{\&Psi;}}=-[\frac{C_{\mathrm{af}}}{C_{\mathrm{\&lambda;f}}}(\frac{{\mathrm{Fb}}_{\mathrm{lf}}}{{\mathrm{\&lambda;}}_{\mathrm{lf}}}+\frac{{\mathrm{Fb}}_{\mathrm{rf}}}{{\mathrm{\&lambda;}}_{\mathrm{rf}}})L_f\cos {\mathrm{\&delta;}}_w-\frac{C_{\mathrm{af}}}{C_{\mathrm{\&lambda;f}}}(\frac{{\mathrm{Fb}}_{\mathrm{lf}}}{{\mathrm{\&lambda;}}_{\mathrm{lf}}}+\frac{{\mathrm{Fb}}_{\mathrm{rf}}}{{\mathrm{\&lambda;}}_{\mathrm{rf}}})L_s\sin {\mathrm{\&delta;}}_w]({\mathrm{\&delta;}}_w-{\mathrm{\&beta;}}_f)\\ +\frac{C_{\mathrm{ar}}}{C_{\mathrm{\&lambda;r}}}(\frac{{\mathrm{Fb}}_{\mathrm{lr}}}{{\mathrm{\&lambda;}}_{\mathrm{lr}}}+\frac{{\mathrm{Fb}}_{\mathrm{rr}}}{{\mathrm{\&lambda;}}_{\mathrm{rr}}})L_r{\mathrm{\&beta;}}_r+({\mathrm{Fb}}_{\mathrm{lf}}+{\mathrm{Fb}}_{\mathrm{rf}})L_f\sin {\mathrm{\&delta;}}_w\\ +({\mathrm{Fb}}_{\mathrm{lf}}-{\mathrm{Fb}}_{\mathrm{rf}})L_s\cos {\mathrm{\&delta;}}_w+({\mathrm{Fb}}_{\mathrm{lr}}-{\mathrm{Fb}}_{\mathrm{rr}})L_s\end{array};$

Wherein, the quality that m is vehicle, V _ythe cross velocity of vehicle, for the transverse acceleration of vehicle, V _xfor the longitudinal velocity of vehicle, for the yaw velocity of vehicle, Fb _lf, Fb _rf, Fb _lr, Fb _rrbe respectively the size of the near front wheel, off front wheel, left rear wheel and off hind wheel braking force, λ _lf, λ _rf, λ _lr, λ _rrbe respectively the size of the near front wheel, off front wheel, left rear wheel and off hind wheel slip rate, C _af, C _arbe respectively the cornering stiffness of front and back wheel, C _{λ f}, C _{λ r}be respectively the longitudinal rigidity of front-wheel and trailing wheel, δ _wfor the deflection angle of wheel, J _vfor the rotor inertia of vehicle, for the yaw angle acceleration/accel of vehicle, β _f, β _rbe respectively the tyre slip angle of front-wheel and trailing wheel, L _f, L _rbe respectively the wheelbase of vehicle front and back wheel, L _sfor the half of car gage.

4. system according to claim 1, is characterized in that,

Described electric machine controller, also for according to the instruction of described vehicle ECU unit, in the time that Vehicular turn is not enough, increases the braking force of inside rear wheel wheel hub motor; Excessive when Vehicular turn, increase the braking force of outside front-wheel hub motor and reduce the speed of automobile; And in the time that vehicle travels on the road surface lower than threshold value at adhesion value, reduce the braking force of the larger side wheel hub motor of braking force.

5. according to the system described in claim 1-4 any one, it is characterized in that, this system also comprises:

Driving console, in the time that described electric machine controller is controlled wheel hub motor, described vehicle ECU unit informs that by described driving console chaufeur is just carrying out the stable control of vehicle body.